From 836b2fe544a5e9b5ce116622cb36fba33838c6fd Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 01:33:23 -0700 Subject: selftests/bpf: Check that JMP32 pointer vs zero jumps are not predicted Add jmp32_ptr_vs_zero_jne: the fall-through of the 32-bit compare, which the verifier used to skip, contains an out of bounds map value access, hence w/o the previous patch the program is accepted. See previous patch for detailed description. Reported-by: Nicholas Carlini Suggested-by: Nicholas Carlini Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/bpf/20260904083325.2083493-6-eddyz87@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- tools/perf/util/cacheline.h | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 tools/perf/util/cacheline.h (limited to 'tools/perf/util/cacheline.h') diff --git a/tools/perf/util/cacheline.h b/tools/perf/util/cacheline.h new file mode 100644 index 000000000..fe6d5b60a --- /dev/null +++ b/tools/perf/util/cacheline.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef PERF_CACHELINE_H +#define PERF_CACHELINE_H + +#include + +int __pure cacheline_size(void); + + +/* + * Some architectures have 'Adjacent Cacheline Prefetch' feature, + * which performs like the cacheline size being doubled. + */ +static inline u64 cl_address(u64 address, bool double_cl) +{ + u64 size = cacheline_size(); + + if (double_cl) + size *= 2; + + /* return the cacheline of the address */ + return (address & ~(size - 1)); +} + +static inline u64 cl_offset(u64 address, bool double_cl) +{ + u64 size = cacheline_size(); + + if (double_cl) + size *= 2; + + /* return the offset inside cacheline */ + return (address & (size - 1)); +} + +#endif // PERF_CACHELINE_H -- cgit v1.3.1